The present invention relates to inflatable work shelters for another structure and in particular to temporary shelters for use in the maintenance of aircraft engines in the open, or for use with other equipment and units.
One of the major problems with aircraft engine maintenance is that very often the aircraft engine has to be repaired in situ. This may be because either there is not hangar space available, or, for example, the particular airline as is becoming the normal practice has flown their own maintenance crew out to maintain or replace the engine, whose own maintenance crew does not have covered facilities or hangars to store the aircraft for maintenance, or alternatively, the cost of such storage is prohibitive. There is thus a need for a temporary structure that would cover portion of the aircraft to at least encapsulate the engine pod below the wing to which it is attached giving sufficient covered spaced beneath the wing to allow the maintenance staff to work thereon in reasonable comfort.
It has always been appreciated that it would be virtually impossible to build any temporary structure around and beneath the wing of the aircraft which would achieve this function because of the relatively high winds and adverse conditions encountered in airports. The amount of damage that could be caused by such a structure being blown over or falling could be considerable. The damage might not alone be to the aircraft to which it was attached or mounted beneath, but to adjoining aircraft and even more importantly to personnel. Thus, it has been considered heretofore as being relatively impossible to provide such a structure.
Similar problems arise with equipment attached to the outside of buildings or other structures. Equipment such as switchgear, boilers, power units and meters for services are often for safety, access and other reasons placed outside buildings. The enclosures, if any, in which they are placed are often insufficient to provide protection from the elements for those working on them.
The problem has been appreciated particularly for construction projects that are being built under extremely adverse environmental conditions of, for example, building gas and oil pipelines across difficult terrain. It has been appreciated for many years that one of the best ways of providing such protection is to use some type of inflatable portable structure or shelter which could be used by personnel working under such conditions. The advantage of this is that as the particular building or unit is constructed the shelter can be deflated and removed to another site. Indeed it has been known to provide such inflatable shelters for fishermen and some maintenance personnel. A typical example of such a structure is described in U.S. Pat. No. 4,192,105 (Morgan). However, to provide such an enormous structure to enclose a whole aircraft would be virtually an impossible task and thus heretofore it has been considered that even if temporary structures were required that inflatable shelters would be inappropriate in situations such as that envisaged above namely for the maintenance of aircraft engines in situ where shelter around the aircraft appears to make it totally impractical in use.
The present invention is directed towards providing an inflatable shelter for mounting beneath the wing of an aircraft to at least encapsulate an engine pod, but also for mounting against or beneath another structure to enclose portion of it to provide protection from the environment for equipment and personnel when work is being cared out on the structure.
Ideally such a shelter should also be capable of being used as a free standing enclosed shelter or building in its own right when not attached to another structure.
Indeed the invention is also directed towards providing temporary structures generally.
According to the invention there is provided an inflatable temporary work shelter for another structure, the shelter comprising walls, at least portion of which are inflatable to provide a free standing shelter characterised in that the walls define an open structure embracing spine having side edges urged on inflation towards each other into a closed position with portion of the structure enclosed therein. The advantage of this is that as well as the inflatable shelter only having to be sufficiently large to encapsulate the portion of the structure that it is desired to work on, it also has the advantage of using the structure to partially anchor it in position. By the spine engaging an embracing portion of the structure, the inflatable nature of the shelter ensures a close contact between the side edges of the spine and the structure thus providing a seal preventing the ingress of dirt, moisture and other contaminants. Thus an enclosed shelter can be provided and if it is necessary to provide heating, air conditioning or the like within the shelter, this can be readily easily provided in an energy efficient manner.
Ideally, the side edge faces are urged on inflation to contact the structure. By having the side edge faces contact the structure suitable anchorage and sealing from the ingress of dirt and moisture or indeed the prevention of, for example, the outflow of hot air will be readily easily achieved. Ideally, portion of the side edge faces contact each other on inflation to surround part of the structure. In one embodiment of the invention, portion of the side edge faces contact each other intermediate their ends to accommodate portion of the structure projecting therethrough.
Ideally the walls comprise a framework formed by inflatable interconnected frame members and a covering material attached thereto, the spine being provided by two adjacent facing bearing frame members. This particular structure is very useful as the facing bearing frame members will form a tight grip against the structure.
Ideally, the spine member comprises a pair of arcuate elongate facing bearing frame members forming on inflation a structure receiving hole, the side faces being urged on inflation to contact the structure. This can be a particularly advantageous arrangement where, for example, an aeroplane has an engine pod which is not, for example, suspended from the engine wing by a pylon but is in effect formed substantially integral with the wing. In this case it is necessary to inflate the structure so that it can encompass the whole of the engine pod and bear up against the underneath portion of the wing. This could be particularly important, for example, where the engine includes cowling of the gull-wing type which cowling when open lies along the underneath the wing and thus the hole might have to be sufficiently large to accommodate not just simply the engine itself but also be sufficiently wide as to allow the cowling lie within the shelter or alternatively for the structure to lie or bear up against the underneath of the gull-wing cowling.
Ideally each bearing frame member includes at least one hinge portion intermediate its length for limited pivotal movement about itself. The advantage of this is that the side edges of the spine will accommodate irregularities and changes in shape of the structure against which it is mounted thus providing an even closer contact between the side edges of the spine and the structure than if no hinges were provided.
In one embodiment of the invention, each bearing frame member comprises a plurality of separate frame members interconnected by extension sheet material to permit extension of the peripheral dimensions of the spine portion to accommodate the structure. Again the advantage of this is that, as will often be the case, the structure to which the shelter is being attached will be relatively large and thus the spine opening might not of itself be sufficient to encapsulate the portion of the structure. This will allow greater flexibility in mounting.
Ideally the two bearing frame members are configured to contact each other firmly on inflation when the structure is not encapsulated therein. The advantage of this is that the shelter, when not used in conjunction with another structure, will form an enclosed shelter or building in its own right.
In one embodiment of the invention, the spine comprises a pair of elongate in-line transverse frame members, each frame member terminating in an end portion bearing against one of the side edge faces, the two end portions facing each other from opposite side edge faces. The advantage of this construction is that the spine forming frame members will, as it were, bear tightly against a structure providing further anchorage and sealing of the side edges of the spine against the structure.
Ideally, the spine is located against the uppermost portion of the shelter when inflated whereby on being placed beneath a structure and inflated the shelter will contact the underneath of the structure and force the side edge faces apart to encompass portion of the structure.
Ideally, the shelter comprises elongate frame members of substantially tubular flexible material and having on the exterior thereof anchorages, and a connecting means for securing in line anchorages together to varying the length of the frame member. The advantage of this is that it is possible to accommodate different heights of plane wing, for example, when the shelter is used in conjunction with engine maintenance.
Ideally the side edges of the spine incorporate a resilient material which resilient material is preferably a foamed plastics material. It will be appreciated that sealing the side edges of the spine against the structure will be advantageous.
In one embodiment of the invention, peripherally arranged extension walls of flexible material are provided to accommodate different heights of structure above the ground. It will be appreciated that, for example, if the shelter according to the present invention is used with various aeroplanes that by virtue of the different constructions of airplane that the height of the airplane wing above the ground will vary and thus the shelter may have to accommodate many sizes and heights of airplane engine above the ground. This equally well applies to other structures. By providing, as it were, planar walls on the lower portion of the shelter, it is possible to accommodate such height variations.
Ideally the side walls incorporate containers for ballast anchoring material which generally will be water. This is particularly advantageous because as well as anchoring the shelter against the structure by means of the spine and its side walls gripping the structure, further anchorage is provided. This will be particularly important where it would not be possible to, for example, insert anchorage spikes or the like into the ground to secure the shelter in position.
In one embodiment of the invention, there is provided connections on the exterior thereof for connection to stay wires. This can be particularly advantageous in situations where high winds can be encountered. The stay wires can be anchored, for example, by any suitable weights on a runway such as sandbags.
It will be appreciated that ideally the walls are substantially arcuate in shape and the spine forms a central ridge for enclosing an aircraft engine pod mounted on the aircraft wing. One of the major advantages of the shelter according to the present invention when used with an aircraft engine or the like structure which is spaced apart above the ground is that the inflatable shelter can be placed beneath, for example, the engine pod, inflated until the spine is directly below the engine pod so that the spine will then engage the pod and on further inflation will slide as it were around the pod to engage over the engine pod on portion of the wing structure. While in many instances a certain amount of manipulation of the shelter around the engine pod may be necessary it will not always be the case and indeed it is envisaged that one person could inflate the shelter and anchor it securely against an aircraft engine pod, the shelter being effectively self locating.
In one embodiment of the invention, it is envisaged that it would be advantageous to provide a plurality of deflation valves adjacent the spine. Since the shelter will encompass and lie over in many instances considerable portions of another structure a problem could arise on deflation in that the shelter would collapse on top of the other structure with portions of it still inflated and be prevented from deflation by pressure, as it were, from part of the other structure bearing against it. It is thus envisaged that additional deflation valves may be required and indeed it is envisaged that such deflation valves may be remotely operated.
In one embodiment of the invention, the shelter walls comprise four upstanding substantially rectangular side walls and a flat covering wall providing a roof and a spine extending from one side wall across the roof to the opposite side wall for an aircraft wing to project therethrough. This is a particularly suitable construction for use with engine pods and aeroplanes where the engine pod is substantially flush with the aeroplane wing.